1. Field of the Invention
The present invention relates to a silver halide color photographic light-sensitive material which contains an emulsion chemically sensitized with at lease one of a selenium sensitizer, a gold sensitizer and a sulfur sensitizer, and also containing a novel compound which releases a development inhibitor, and which has high sensitivity and excels in image-quality.
2. Description of the Related Art
There is a demand for a silver halide color photographic light-sensitive material (hereinafter called light-sensitive material), particularly one for photography use, which has a high light-sensitivity and stable photographic properties and which excels in image quality (color reproduction, graininess, and sharpness).
Known as means for improving the color reproduction and sharpness of such a light-sensitive material is a timing DIR coupler which releases a development-inhibiting compound through two timing groups. DIR couplers of this type are disclosed in, for example, JP-A-51-146828 ("JP-A" means Published Unexamined Japanese Patent Application), JP-A-60-218645, JP-A-61-156127, JP-A-63-37346, JP-A-1-280755, JP-A-1-219747, JP-A-2-230139, and Laid-open European Patent Applications 348139, 354532 and 403019. The use of a timing DIR coupler indeed enhances inter-layer effect or edge effect, thereby improving the sharpness and color reproduction to some extent. However, neither the inter-layer effect nor the edge effect can be sufficient since the development inhibitor is released substantially in a single step at an improper timing. Further, the light-sensitive material is disadvantageous in its stability, e.g., the stability during storage or the stability of its photographic properties during processing.
In general, a silver halide emulsion for use in light-sensitive materials is subjected to chemical sensitization using various chemicals, in order to have a desired sensitivity or a desired gradation. Known as typical examples of chemical sensitization are sulfur sensitization, selenium sensitization, gold sensitization, reduction sensitization, and any combination of these sensitizations.
These sensitizations have been improved in various respects in order to enhance sensitivity and graininess.
Of the sensitization methods described above, selenium sensitization is disclosed in, for example, U.S. Pat. Nos. 1,574,944, 1,602,592, 1,623,499, 3,297,446, 3,297,447, 3,320,069, 3,408,196, 3,408,197, 3,442,653, 3,420,670 and 3,591,385, French Patents 2,693,038 and 2,093,209, JP-B-52-34491 ("JP-B" means Published Examined Japanese Patent Application), JP-B-44-15748, JP-B-52-34492, JP-B-53-295, JP-B-57-22090, JP-A-59-180536, JP-A-59-185330, JP-A-181337, JP-A-59-187338, JP-A-59-192241, JP-A-60-150046, JP-A-60-151637, JP-A-61-246738, British Patents 255,846 and 861,984, and H. E. Spencer et al., "Journal of Photographic Science," Vol. 31, pp. 158-169 (1963).
Generally, selenium sensitization can sensitize an emulsion more effectively than sulfur sensitization which is usually performed in this field of industry, but there is a problem that it leads a light sensitive material to fog and soft gradation. Further, it may result in a decrease in the stability of the light-sensitive material during storage or processing, depending on the compound used as selenium sensitizer.